Microstructural and mechanical properties of tungsten carbide (WC)-reinforced 316L stainless steel composites fabricated by binder jetting additive manufacturing

The binder jetting (BJ) additive manufacturing technique for fabricating ceramic-reinforced metal matrix composites has been scarcely explored in the existing literature. This research focuses on the integration of tungsten carbide (WC) as a representative ceramic reinforcement within a 316L stainless steel matrix, a common choice for metal matrix applications. A systematic investigation has been conducted to evaluate the impact of WC on the microstructure, mechanical properties, and tribological characteristics of the 316L stainless steel matrix composites produced via the BJ additive manufacturing process. The findings reveal that the introduction of WC significantly improves the rheological properties of the feedstock composite powders, including flowability and stability, and enhances the flexural strength of the green parts post-BJ processing. Following the sintering/infiltration process, the WC-reinforced 316L composites demonstrate a substantial increase in hardness and wear resistance relative to the unalloyed 316L stainless steel. Nonetheless, these composites exhibit a reduction in fracture toughness and transverse rupture strength when compared to the pristine 316L stainless steel.